Experimental determination of the fatigue behavior of dowel strips in ortho‐composite slabs for road bridges

In contrast to reinforced concrete and conventional composite bridges, the orthotropic steel deck slab offers a high load‐bearing capacity combined with a low dead weight. It is therefore ideally suited for slender and long‐span structures. However, the notch sharpness in the details and drastically increased traffic loads led to extensive fatigue damage and, as a consequence, often to premature repair or replacement work. With the ortho‐composite slab a lightweight and robust construction is currently being developed as an alternative. It combines the significant advantages of a low dead weight, long service life and economical production. The construction consists of a modified orthotropic stiffened steel plate and a thin, single‐layer reinforced in‐situ concrete. Composite dowel strips (CDS) with a clothoid shape are provided as shear connectors. In this paper, the experimental test program will be introduced. It comprises static push‐out tests on CDS in longitudinal and transverse directions as well as static and cyclic beam and segment tests. The focus lies on the test set‐ups, sample preparations, measurement concepts and the results of the so‐called beam tests. The investigations presented here were carried out as part of the AiF‐FOSTA research project P1265 [1].